Self-captivating wedge

ABSTRACT

A self-captivating wedge is disclosed which has particular utility in securing idler assemblies onto the side cables of a flexible side frame conveyor and which wedge is formed with a generally wedge-shaped body having a self-captivating means formed at the front end thereof for preventing the wedge from being disengaged from the idler assembly. The self-captivating means consists of a pair of lugs formed on the wedge which extend substantially normal to the sides of the wedge body and a pair of slots formed in the body immediately adjacent, and to the rear of, the lugs. The self-captivating means is specifically designed so as to require a combination of movements in order to insert the front of the wedge into the aperture which captivates the wedge and the lugs are further designed so as to create an interference fit as the front of the wedge is moved through the above-mentioned aperture.

Edited States Patent Diantonio Feb.22,1972

[73] Assignee: Hewitt-Robins,

Conn.

221 Filed: Feb.24,l970

[21] Appl.No.: 13,380

Incorporated, Stamford.

Primary Examiner-Richard E. Aegerter Assistant ExaminerDouglas D. Watts Attorney-John D. Boos and John D. Lister [5 7] ABSTRACT A self-captivating wedge is disclosed which has particular utility in securing idler assemblies onto the side cables of a flexible side frame conveyor and which wedge is formed with a generally wedge-shaped body having a self-captivating means formed at the front end thereof for preventing the wedge from being disengaged from the idler assembly. The self-captivating means consists of a pair of lugs formed on the wedge which extend substantially normal to the sides of the wedge body and a pair of slots formed in the body immediately adjacent, and to the rear of, the lugs. The self-captivating means is specifically designed so as to require a combination of movements in order to insert the front of the wedge into the aperture which captivates the wedge and the lugs are further designed so as to create an interference fit as the front of the wedge is moved through the above-mentioned aperture.

7 Claims, 8 Drawing Figures PAIENTEDFEBZZ 1912 V 3.643.793

SHEET 1 [1F 2 mvawron DANIEL J. 0/ ANTON/0 ATTORN EY -PATENIEOFEB22 I972 3,643 793 SHEET 2 or 2 INVENTOR 7 DANIEL J. 0/ ANTONIO BY Q/MIZQm ATTORNEY SELF-CAPTIVATING WEDGE BACKGROUND OF THE INVENTION The present invention relates generally to belt conveyors of the type where the conveying reach is supported on flexible strands or side cables and, in one particular aspect, to a novel and improved self-captivating wedge for securing a troughing roller assembly onto the side cables.

Flexible side frame conveyor systems are frequently emplayed in underground mining. In such conveying systems it is conventional for the troughing idler roll assemblies to be supported on tensioned parallel side cables or other flexible side members and for the idler assemblies to be held in position on the cables by wedges or spikes which wedge the cables into mounting brackets on the assemblies. These wedges are sometimes vibrated loose causing the idler assembly to shift and resulting in misalignment of the conveyor belt. In addition, when these wedges are vibrated loose, they frequently become completely separated from the idler assembly brackets and can be easily lost.

Prior art solutions to these problems have been to have a conventional wedge formed so as to receive a second independent locking member which must be inserted after the wedge has been driven into wedging engagement with side cable. These prior art designs double the number of pieces which may be lost, greatly complicate the process of securing the idler assemblies to the side frames, and increase the cost of the wedges.

SUMMARY OF THE INVENTION In carrying out the present invention, a one piece, self-captivating wedge. is provided having self-captivating means formed integrally on the front end of the wedge body. The self-captivating means consists of an unique combination of lugs, or similar projections, formed on the front end of the wedge body and which lugs combine with slots also formed in the wedge body in order to require that a particular sequence of steps be followed for the insertion of the front end of the wedge body through an aperture of a particular size and shape. This aperture can be formed in any member which requires the use of the self-captivating wedge, however, the present application describes this wedge design for use with brackets on idler assemblies. In any event, these relatively complex series of motions required for inserting the wedge through the aperture greatly decreases the likelihood that the wedge will accidentally become separated from the member.

Accordingly, it is one of the objects of the present invention to provide a novel and improved self-captivating wedge design which may be readily installed for securing a troughing roller assembly upon flexible strand side frames.

Another object of the present invention is to provide a novel and improved self-captivating wedge design which is self-captivating once installed within the bracket of a troughing roller assembly.

Still another object is to provide a wedge having a self-captivatin g means formed on the front end thereof.

BRIEF DESCRIPTION OF THE DRAWINGS Although the features of this invention which are considered to be novel are set forth in the appended claims, further details as to preferred practices and as to further objects and features thereof may be most readily comprehended through reference to the following description taken in connection with the accompanying drawings, wherein:

FIG. 1 is a perspective view of a troughing roller assembly secured to flexible strand side frame members;

FIG. 2 is a sectional view along the line 22 of FIG. 1;

FIG. 3 is a perspective view of a first embodiment of the self-captivating wedge of the present invention;

FIGS. 4, 5, 6 and 7 are partial sectional views illustrating the sequential insertion of the self-captivating wedge of the present invention within a bracket member of a troughing roller assembly; and

FIG. 8 is a perspective view of a second embodiment of the self-captivating wedge of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawing wherein like reference characters designate identical or corresponding parts throughout the several views, and more particularly to FIG. 1 thereof, there is shown a troughing idler roll assembly indicated generally by the reference numeral 10 suspended between spaced flexible strand means, or cables, 12 and 14. The strand means are supported in the conventional manner at intervals throughout their lengths upon supports or standards, not shown, each such standard having a U-shaped saddle at the top thereof for receiving the flexible strand means. As is conventional in such structures, an endless conveyor belt, not shown, is supported upon spaced troughing idler roll assemblies during its conveying path or conveying reach and secured to the frame of the troughing roller assembly by con- 7 ventional means, such as welding.

A pair of horizontally extending brackets 24 secured to the outer base portions of the troughing roller assembly support the assembly on the flexible strand means 12 and 14 in such a manner that the troughing roller assembly can be removed from the strand means or adjusted in position thereon as desired. Brackets 24 include a pair of limbs 26 and 28 which straddle the flexible strand means. The two limbs 26 and 28 are connected by a bight 30 which forms a saddle for seating the flexible strand means.

In the preferred embodiment, each of the brackets 24 is formed with two sets of apertures for receiving the wedge member of the present invention. The first set includes outer aperture 36 and inner aperture 38 formed in limbs 26 and 28 respectively. The second set, indicated generally by reference numeral 40, is identical in shape and form to the first set except that they are positioned at a slightly greater distance from the bight 30. Thus, one common wedge can then be employed, depending on which set of apertures are employed, to clamp different diameter side cables. In this type conveyor it is common to employ side cables which are either five-eighths inch or three-fourths inch diameter; however, it will be obvious that the sets of apertures can be positioned for almost any diameter cable and any number of sets of apertures could be formed in each bracket if the bracket were to be employed with cables having a number of different diameter cables.

As seen more clearly in FIGS. 3 and 7, the wedge member 32 has an elongated wedge-shaped body 42, which is preferably formed with a flat bottom surface 42A, flat side surfaces 42B, 42C normal to the bottom surface, as shown in FIG. 7, and an inclined wedging surface or top face 42D. Formed integrally with body 42 is the rear end section 48 having tabs 50 extending outwardly from, and substantially normal to, the side surfaces of the body. The front end of body 42 is formed with substantially coaxial lugs or bosses 52 extending outwardly from, and substantially normal to, the side surfaces of the body. Directly adjacent to, and to the rear of, each lug is a curvilinear fillet 44, which is formed by a slot or undercut section 46 in body 42, which extends from the base surface to the side surface from which the respective lugs project. The width of each of the slots 42 are slightly wider than the thickness of limb 26, as can be seen in FIG. 2, so as to thereby enable the wedge member to be rotated, as shown in FIG. 6, into the FIG. 7 position where the side surfaces of the wedge member are positioned extremely close to the sides of the eutout. Each of the lugs are sized (i.e., the length and diameter or thickness) so that when either of the lugs are inserted through the cutout with the centerline of the lugs extending substantially diagonally across the square cutout, as illustrated in FIG. 4, the second lug creates an interference fit with the opposite corner of the cutout. This second lug may then be forced or hammered through the cutout into the position illustrated in FIG. 5.

The wedge member is preferably cast in one piece out of malleable cast iron. The hardness of the iron is selected so that it is somewhat softer than the normal surface hardness of the wire rope cable and in this manner any wear will tend to occur on the wedge rather than on the cable. The wedge can be cast as a solid member with only one wedging surface, not shown. However, the presently preferred design provides two separate, and substantially identical, wedging surfaces 42D, 42D by having a blind slot 19 formed in the top surface of the body. This particular design reduces the amount of material in the casting and at the same time provides two separate wedging surfaces which contact the wire rope cable and which appear to improve the clamping action of the wedge.

Referring now to FIGS. 4 through 7 wherein the method of installing the wedge of the present invention is shown sequentially, the first step in the installation procedure is to insert one of the lugs 52 on the front edge of the wedge through aperture 36 while holding the wedge in a diagonal position, as shown in FIG. 4. The wedge is subsequently forced or driven into the position shown in FIG. wherein both of the bosses or lugs 52 are hooked within aperture 36. Referring to FIG. 6, the wedge is oriented with the slots 46 in alignment with the wall portion of aperture 36 such that the wedge can be subsequently rotated to the position shown in FIG. 7. The wedge is then inserted through the second aperture 38 and then forced into wedging position against the bottom of the side cable. In order to release the wedge from the wedging position, it is simply necessary to hit or otherwise force the front end of the wedge rearwardly so as to release the wedge from engagement with the cable. In order to entirely remove the wedge from the bracket it is necessary to position the wedge with the lugs extending diagonally across the aperture 36, as shown in FIG. 5, and then apply a force to the wedge such that one of the lugs is forced through the aperture, thereby releasing the wedge.

It will be apparent from the above description that the wedge becomes self-captivated when it extends through aperture 36 with both lugs 52 on one side of limb 26 and with tabs 50 positioned on the other side thereof. The tabs 50 serve to prevent the rear end of the wedge from accidentally sliding through aperture 36 when the bracket is not positioned around a cable 12 as shown in FIG. 2. Likewise, lugs 52 similarly prevent the front end of the wedge from being accidentally withdrawn through the aperture. Thus, lugs 52, slots 46, and tabs 50 combine to provide the wedge with a captivating means for preventing the wedge from accidentally falling out of aperture 36 in the bracket. If the rear end 48 of the wedge is sufficiently large so as to prevent passage of the entire wedge through aperture 30, then tabs 50 can be eliminated.

The combination of lugs 52 and slots 46 provide a front captivating means which requires the wedge to be inserted into bracket aperture 36 by following the specific series of relatively complex steps described above. In order to remove the wedge from the bracket, it is necessary to substantially reverse these steps. It will be apparent that the number and complexity of these steps substantially reduce the likelihood that the wedge will accidentally become separated from the bracket. It will also be noted that the front captivating means described above can be sized so that each of these steps can be performed with very little force required; however, the lugs in the preferred embodiment are sized so that an interference fit must be overcome when the front end of the wedge is fully inserted or retracted from the bracket. The interference fit is an additional factor which reduces the likelihood of the wedge becoming accidentally separated from the bracket.

It should also be noted that the front captivating means on the front end of the wedge achieves this self-captivating feature and yet enables the width of the wedge to be made only slightly smaller than the width of the aperture as shown in FIG. 7. Thus, once the idler assembly is coupled to the wire rope cable, any shifting of the mounting bracket relative the wedge will be limited to the very small distance between the sides of the wedge and the sides of the aperture. The side of the aperture will thereafter come in contact with the side of the wedge and any further slippage of the bracket will require both the bracket and the wedge to be moved relative the wire rope cable.

The preferred embodiment, shown in F116. 1, employs one type of wedge on a bracket having two sets of apertures spaced at different distances from bight An alternate aperture arrangement for these brackets is to have a single set of apertures and employ different wedges with different iiiciud ed angles in order to clamp different diameter cables. Aiternatively, one wedge can be designed to clamp more than one diameter cable even though the wedge is being employed with a single set of apertures. For example, it will be apparent that the wedge shown in FIG. could be retracted outwardly a small distance and thereby enable it to clamp a larger diameter cable. Thus, each wedge has an effective length a," as shown in FIG. 2, throughout which it can effectively clamp a cable and it is simply necessary to design the wedge such that the effective length will be able to cooperate with a single set of apertures and clamp cables for a preselected range of cable diameters. If it is found that a large portion of the effective length at the front end section of the wedge is never required for clamping, it will be apparent that the resulting wedge will be unnecessarily long in length. This unused portion of the effective length can be reduced, as s town in FIG. 8, by having a transition section 56 extend from the edge of the slot to the base. By having the transition section provided with an inclined ramp id, it is possible to have the unused portion of the effective length greatly reduced and provide a smooth transition from the front captivating means to the base of the wedge.

It is to be understood that the abovemlescribed embodiments are simply illustrative of the application of the principles of this invention. Numerous other embodiments may be readily devised by those skilled in the art which will embody the principles of the invention and fall within the spirit and scope thereof.

What is claimed is:

l. The combination of a conveyor component and a wedge member, said conveyor component adapted to be secured onto a tensioned side cable of a flexible side frame conveyor, said component comprising a bracket member having a pair of spaced-apart substantially rigid limb portions and a bight portion connecting said limb portions together, a first pair of apertures comprising a first aperture formed in one of said limb portions and a second aperture formed in the other of said limb portions, said apertures being in alignment and receiving said wedge member for securing the tensioned side cable between the intermediate portions of said wedge member and the bight portion of said bracket member, the improvement in said wedge member comprising a pair of lateral projections formed at the front end of said wedge member having undercut portions adjacent to the rear of, said projections which define rounded corners on said wedge member; said projections and said undercut portions combining to form a self-captivating means; the overall width of the front end of said wedge member including the combined length of said lateral projections, being greater than the width of said first aperture such that the front end of said wedge member must be inserted into said first aperture by orienting said wedge member such that one of said projections is first inserted through said first aperture, then moving the wedge member such that the second projection is moved through said first aperture and then rotating said wedge member into an operative position for securing said conveyor component onto said side cable; the undercut portions of said wedge member facilitating the rotation of said wedge member when said wedge member extends through said first aperture.

2. The improvement as described in claim 1 wherein an interference fit is created as the second projection is moved through the first aperture.

3. The improvement described in claim 1 wherein said projections are coaxial with each other and extend out substantially laterally from the sides of the wedge.

4. The improvement described in claim 1 wherein the width of said second aperture is at least as great as the sum of the width of said wedge member and the combined length of said pair of projections.

5. The improvement described in claim 1 wherein each of said limb portions have a second pair of apertures formed in said limb portions which are identical to said first pair of apertures, said second pair of apertures being spaced farther from the bight portion than said first pair of apertures.

6. The improvement described in claim 1 wherein said O inclined wedging surface, a bottom surface, and spaced side surfaces, said inclined surface extending from the rear end of said body down to the front end of said body, the size and shape of the rear end of said body being such that it prevents said wedge member from passing entirely through said first aperture. 

1. The combination of a conveyor component and a wedge member, said conveyor component adapted to be secured onto a tensioned side cable of a flexible side frame conveyor, said component comprising a bracket member having a pair of spaced-apart substantially rigid limb portions and a bight portion connecting said limb portions together, a first pair of apertures comprising a first aperture formed in one of said limb portions and a second aperture formed in the other of said limb portions, said apertures being in alignment and receiving said wedge member for securing the tensioned side cable between the intermediate portions of said wedge member and the bight portion of said bracket member, the improvement in said wedge member comprising a pair of lateral projections formed at the front end of said wedge member having undercut portions adjacent to the rear of, said projections which define rounded corners on said wedge member; said projections and said undercut portions combining to form a self-captivating means; the overall width of the front end of said wedge member including the combined length of said lateral projections, being greater than the width of said first aperture such that the front end of said wedge member must be inserted into said first aperture by orienting said wedge member such that one of said projections is first inserted through said first aperture, then moving the wedge member such that the second projection is moved through said first aperture and then rotating said wedge member into an operative position for securing said conveyor component onto said side cable; the undercut portions of said wedge member facilitating the rotation of said wedge member when said wedge member extends through said first aperture.
 2. The improvement as described in claim 1 wherein an interference fit is created as the second projection is moved through the first aperture.
 3. The improvement described in claim 1 wherein said projections are coaxial with each other and extend out substantially laterally from the sides of the wedge.
 4. The improvement described in claim 1 wherein the width of said second aperture is at least as great as the sum of the width of said wedge member and the combined length of said pair of projections.
 5. The improvement described in claim 1 wherein each of said limb portions have a second pair of apertures formed in said limb portions which are identical to said first pair of apertures, said second pair of apertures being spaced farther from the bight portion than said first pair of apertures.
 6. The improvement described in claim 1 wherein said wedge member has an elongated wedge-shaped body with an inclined wedging surface; said wedging surface being designed to contact the tensioned side cable which is to be secured between the wedge member and the bight portion of said bracket member, the relative hardness of said inclined wedge surface being selected so as to be softer than the surface hardness of the tensioned side cable which is to be secured.
 7. The improvement described in claim 1 wherein said wedge member has an elongated wedge-shaped body with an inclined wedging surface, a bottom surface, and spaced side surfaces, said inclined surface extending from the rear end of said body down to the front end of said body, the size and shape of the rear end of said body being such that it prevents said wedge member from passing entirely through said first aperture. 